Fix #10987: Double-close of dropdown stopped land-info tool working as default. (#11000)

Clicking and releasing on the query toolbar icon is meant to select the land-info tool.

This did not work as during closing a window, OnFocusLost() is called, which then closes the window again. These two calls toggled the land-info tool one and off in the same action.

Resolve by not calling Window::Close in OnFocusLost() if the window is already closing.

src/osk_gui.cpp

@@ -197,10 +197,10 @@ struct OskWindow : public Window {
 		this->parent->SetWidgetDirty(this->text_btn);
 	}
 
-	void OnFocusLost() override
+	void OnFocusLost(bool closing) override
 	{
 		VideoDriver::GetInstance()->EditBoxLostFocus();
-		this->Close();
+		if (!closing) this->Close();
 	}
 };